Synaptic communication and re-uptake / reuptake inhibitors / Adrafinil

Peter F effectivespamblock at ozemail.com.au
Wed Dec 15 10:21:49 EST 2004


"r norman" <rsn_ at _comcast.net> wrote in message news:9me0s0l1j43obterjkrcudnmui54drc51b at 4ax.com...

> After a pre-synaptic neuron releases its transmitter and it acts on
> the post-synaptic receptors, there are three different mechanisms to
> eliminate the transmitter.  First, there may be enzymes in the
> extracellular space (attached to the membranes of either neuron) that
> break down the transmitter.   Second, there may be transport proteins
> in the presynaptic membrane that take the transmitter back into the
> presynaptic cell.  This is the reuptake mechanism you describe.
> Similarly, there may be transport proteins that take the transmitter
> into nearby glial cells.  Third, the transmitter might simply diffuse
> away making its concentration so low that it is no longer effective.
> These can also work in combination.
> 
> All these act in a time frame measured in milliseconds.  After some
> tens of milliseconds, the transmitter is completely removed from the
> synaptic region.  The duration of synaptic action is normally much
> shorter than the duration of the post-synaptic effect.  That is, the
> post-synaptic potential far outlasts the presence of synaptic
> transmitter.  
> 
> In synapses where reuptake is the primary removal mechanism, reuptake
> inhibitors allow the transmitter to persist in the synaptic space for
> a much longer time than normal and hence to produce a much increased
> response.  "Much longer" means  only many more milliseconds.  The
> times are nowhere near the seconds and hours you mention. 

Richard,

What do you make of the time-scale for the action of neuromodulators (e.g. substance P or endorphins), then?

Is it possible for you (the way it is for me -- percEPTive as I am) to observe something similar to the ~minutes-long~  "drugged" psychophysical after-effect 
of opioidergic activity after a lengthy (conceptually challenged as I am, and concEPTually challenging as I am _trying_ to be)
intellectual type preoccupation  (that I would not say is "never inEPT')?

Peter


-- 
Partly inspired by MAD (cold war shaming acronym), I arrived at EPT
[e.g: eclectically Explanatory perversely Pert
philosophical Terminology] and by concEPTual lenses/tools saw/grasped how
and why AEVASIVE preoccupations (personalities) normally preclude making
in dEPTh sense (of themselves).
In the acronym for Ambiadvantageously Evolved 'V-word' Actention
Selection (System) Involving Various Endorphins, AS(S) stand for how we
think/emote/behave based on our individual repertoire of competing {by
mutual inhibition) whilst cheered and booed {by current and past
environmental influences) "actention modules", & AE refer to the didactic
division of the Evolutionary Pressure Totality into relevant dialectic
lifetime juxtapositions of:
1. Opportunity
2. Adversity - here especially SHITS [Synaptic Hibernation Imploring
{naturally selective AND 'motivating' of selective unconsciousness)
Traumatic {also tardily so) Situations] normally repercussively retained as
CURSES type memory aka "Pain" (Janov)


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